The present invention relates to a piece of furniture. More particularly this invention concerns a recliner chair that can be moved into a stand-assist position making it easy to get out of the chair.
A standard recliner chair comprises a base frame that typically sits on the floor, a seat frame carrying a generally horizontal seat cushion, a back which may be fixed on the seat frame or pivot relative to it, and in some instances a footrest that can also pivot relative to at least one of the frames. Such a chair is typically movable between a standard sitting position with the back and footrest generally vertical and a reclining position with the back and footrest much more horizontal and the upper end of the back slightly above the footrest. Often in the reclining position the seat is also inclined somewhat downward from the inner edge of the foot rest to the lower edge of the back for comfort. Variations on the reclining position place the upper end of the back well above the footrest for watching television or reading, or placing the upper end of the backrest level with or below the footrest for cardiovascular purposes.
It is also known for example from U. S. Pat. No. 5,265,935 for a stand-assist chair to have a base, front and back wheels on the base normally supporting it rollably on a floor, a seat having a front edge and a back edge, a back extending upward from the back edge of the seat, and a pair of lever systems engaged between the seat and the base operable to displace the seat between a normal sitting position with the seat front edge somewhat above the seat rear edge and a stand-assist position with the seat rear edge somewhat above the seat front edge and the entire seat elevated above the level it occupies relative to the base in the normal sitting position. A drive motor is engaged with the lever system for displacing the seat between its positions. A pair of feet are movable on the base between a retracted position above a plane defined by lowermost surfaces of the wheels and an extended position projecting downward past the plane and lifting at least one of the wheels off the floor. Links are connected between the lever systems and the feet for automatically displacing the feet into the extended position when the seat is in the stand-assist position.
Such systems are typically driven by a pair of shafts that must withstand the considerable forces they exert via the various lever systems on the seat, back, footrest, and frame. There is a tradeoff therefore between expensive sturdy construction certain to have a long service life and cheaper less robust design likely to lead to failure. Furthermore the chairs cannot readily be brought into any of several different positions, such as the full-rest position with the footrest level with or even slightly above the head.
It is therefore an object of the present invention to provide an improved stand-assist recliner chair.
Another object is the provision of such an improved stand-assist recliner chair which overcomes the above-given disadvantages, that is which is of robust but simple and inexpensive construction and which can assume a plurality of different positions.
A stand-assist chair has according to the invention a base frame adapted to stand on the floor, a seat frame movable above the base frame and carrying a generally horizontal seat, a back on the seat frame extending transversely upward from a rear edge of the seat, and a motor housing on one of the frames. Front and back actuating shafts are journaled in the motor housing under front and rear edges of the seat and have respective front and back actuating arms and respective front and back operating arms. The front arm has an outer end pivoted on the other of the frames adjacent a front edge of the seat and the rear arm has an outer end operatively coupled to the other of the frames adjacent the rear seat edge. A drive includes respective independently operable front and rear motors connected to the actuating arms for rotating the respective shafts so as to move the front and rear seat edges independently of each other between respective lower, intermediate, and upper positions so that the chair can assume a sitting or reclining position in the lower positions of the seat edges, a stand-assist position in the upper positions of the seat edges, and other positions in the intermediate positions of the seat edges.
The use of independent motors allows the chair to assume several different positions since in each of the lower, intermediate, and upper positions of one of the shafts, the other shaft can be in the lower, intermediate, or upper position, making it technically possible to assume nine different positions. Normally the most useful positions are the sitting position in which both the shafts are in their lower position, and the described stand-assist position in which both the shafts have pivoted their arms to the respective upper positions. The intermediate positions are used for reclining, cardiovascular full rest with elevated feet, or even reclining but with the head up for watching television or reading.
The drive assembly is largely self contained and the two shafts, which can be positioned horizontally well apart for good mechanical advantage and excellent stability of the chair, are held at a fixed spacing from each other so that they will not bend. The system can be built of relatively light materials and still be very strong since the end walls of the housing, in which the shafts are journaled, are stressed purely in tension.
In accordance with the invention the one frame is the seat frame and the other frame is the base frame. In this case the front operating arm has an outer end and the base frame includes an upright having an upper end directly pivoted to the front-arm outer end. Furthermore there is a rigid link between an outer end of the rear arm and the base frame.
In another system according to the invention the one frame is the base frame and the other frame is the seat frame. In this case the seat frame has front and rear brackets. The front arm has an outer end pivoted directly on the front bracket and a rigid link is provided between an outer end of the rear arm and the rear bracket.
Normally according to the invention the front shaft carries two such front arms and the rear shaft carries two such rear arms. Furthermore the front arms have a shorter effective length than the rear arms so that in the stand-assist position the seat is tipped forward and down.
The housing in accordance with the invention is cup-shaped, downwardly open, formed with front and rear slots fitting over the shafts, and provided with front and rear covers closing the slots around the shafts. In addition in the sitting position the shafts are generally level with each other and the actuating arms are generally vertical.